Sounds like the dealer I went to about my transmision temperature. Called and said this truck isnt fixed, first trip trans got to 214 empty in stop and go traffic!

Dealer: Yeah that is within the limits according to Ford, theres nothing we can do!

Me: OK well it never ran much over 190 before you guys rebuilt it so something is screwed up somewhere!

Dealer: Sorry nothing we can do, Ford engineers say it's OK!!

Me: You guys are clueless, I will be taking this problem straight to the top since you are no help!

Sorry for the rant!!

I'm with you, my F-350 SRW will only get 16-17 around town. If I reset the Lie-O-Meter on the interstate and it will hang out around 17.5 @ 75. Wish I was getting what some of these guys are!!

 

I will second your results. Mine our almost exactly the same. Well, except I was getting less than 12 mpg unloaded. Maybe 10.5 but my 6.4 was a dually.

Sometimes we all have to be more realistic, and if you cannot, then consider buying a 6.4 and really get pissed! I am planning a couple more trips this year with the increased mileage, and hopefully a little more after I install my hard tonneau bak flip.

Rich

 

Pardon me asking this, I couldn't tell from your posts if your MPG calculations are done by hand or by using the onboard fuel calculation? I just did my first fill-up and noticed a difference between the onboard calculator and my pencil & paper calculation. It got me thinking about your situation.

If you are using the onboard system, the difference could be related to a change they may have made in the calculation. Often these "flashes" include other changes that a lot of the time go by undiscussed.

It is hard for me to understand why a manufacturer would knowningly make a change to lower MPG. Then again, it is not unheard of a manufacturer making a mistake and correcting it later...

As for my calculations, after the first tank I am averaging 14.8 (provided the dealership topped it off) and the onboard system is saying 16.1.

 

I have seen a few descriptions of what the IDS acronym is but whatever the exact words are is not important. IDS is the computer program that Ford Motor Company uses to support the dealer with program updates and information on their
cars and trucks. It runs the diagnostics that are available through the OBDII port under your dash. It reprograms the trucks computers. Yes, it really is the "Strategy" BTDT. Same system is used on all Ford vehicles to diagnose and reprogram. Different programs for each vehicle series.

Thanks for the reps

Merry Christmas

 

Just a couple comments:
First, we all must remember to reset the mpg computer after a fill up.

Second, I find it so nice that when you fill up your truck you do not have to waste time putting in the last 5 gallons. It seemed like it took forever to top off the tank on the 6.4. Now, the fuel handle clicks once, I top off, and that is a full tank. LOVE IT. (if you never had a 6.4 you will not understand)

 

and I don't have that problem on my 6.4, LB. works same as yours does now.

Sam

 

My 6.4 was a job 2, with a 38 gallon tank on long bed, KR. What is yours?

Or, did you harpoon your tank?

 

I see that Nipperdog is running 3:55 rear end, what are you running? I have the 3:31 in mine. Ordered it that way because that is what Ford was using out in Arizon during the time they let all the press drive them for the first drive articles, when they were reporting the great fuel milage ( I remember one report that claimed the author got around 27 mpg ). Rear end makes a differance.

I have always used the lie-o-meter for my fuel calculations, that way I have a constant referance.

 

Mines a Job 1, 38 gallon tank. I bought it used, but based on prior owner records he didn't do anything, and I haven't.

I ran it down to 2 miles til empty (not planned) and put just over 35 gallons in it on full fill rate to the first click. (rumor has it you can't get the last 3 gallons thru the stock fuel pickup)

Sam

 

I have found the fuel computer to be quite accurate. In 45 gallon fill ups since installing my Titan tank, it has never been off more than a gallon or so. Close enough for me.

Merry Christmas

 

I do it all on paper, the on-board is just an estimate. Given the amount of people who have this same problem, it looks like it's a bad program. But the decrease would make sense given that were' making more power, an I doubt that power is from an efficiency gain.

 

I have to ask, what is a large amount of people with the same problem? I have followed this drive train since April. I was an early recipient of the 400/800 update, installed the day it was universally available. I have put on 9000 miles since then.My mileage increased after the reflash, until winter fuel appeared. My situation is not unique. Yours is though. A competent Ford service technician can get to the real issue. The problem with that is they can be hard to find at times. Good luck

Merry Christmas

 

One of the claims that Ford published for the 400/800 re-flash was a small increase in economy due to slightly higher HP, improved transmission shift strategy, and using the power to enable the vehicle to cruise at speed with a lower percentage of engine load which requires less fuel.

I hate to hear of your problems guys. My 6.7 has lost some economy but I know for a fact it is caused by colder weather, winter fuel, and strong headwinds with all these fronts moving around. I just drove from Topeka, KS to my home which was 1025 miles (pulled an all niter) and I had the worst economy ever seen by my truck. At times it was as low as 9.3. That's what I got with my 6.4 I had.

I use the computer, no hand calc.

 

I'm just doing the numbers. I.e. there are a few instances of this happening amongst those who have responded to this thread and if you transpose that percentage onto the number of trucks on the road you end up with what is actually a significant number. Granted, it looks like the majority, like yours, don't have this problem but if you simply do the math there are numerically a lot of people who do. Guess it's worth noting that I have a masters in mechanical engineering so my life is somewhat numerically driven and think in terms of numbers.

 

Rickatic:

I have to agree with you. While we have absolutely no numbers we have followed the 6.7 for about a year. I forget when the first engines were sold, presumably because of the 2010 compliance issues, for sure in 2010.

If my truck starts to act up like High Binder's problem, I would get a Ford garage to check things out. He shows a F-250 and as such, covered by the fuel consumption notices.

Also, on one of the posts it was discussed in detail the QUALITY of the fuel we buy. I firmly believe if we could buy 45 CETANE Fuel Oil, with less than 15 ppm sulfur, we all would be happy with the increased mileage!